This project is best considered as a supplement to projects 5200-121 (EST Libraries and Bioinformatics) and 5200-125 (Genetic Maps of Sweet Orange and Trifoliate Orange) which use a new tool, microarrays, to study patterns of gene expression and map genes. Those projects are funded by CRB with matching funds from UC Discovery, but we are not permitted to spend those Discovery funds to purchase the microarrays necessary for the research. This CRB grant supplemented other UC funds and allowed us to purchase the chips needed to conduct the other projects.